What Is Underinsured Motorist?
Underinsured motorist (UIM) coverage pays your medical and related costs when an at-fault driver’s liability limits are too low to cover your damages. It stacks on top of their policy up to your UIM limit. It is paired with uninsured motorist (UM) coverage, which applies when the other driver has no insurance at all.
Why it matters
Minimum state liability limits are often far below a serious-injury bill, so UIM/UM is the coverage that protects you from other people’s thin policies.
Common confusion
UIM applies when the other driver has some but too little insurance; UM applies when they have none. Both are optional in many states despite the risk.
Frequently Asked Questions
Is UIM required?
Some states require UM/UIM, others only offer it optionally. Given low state minimums, carrying it is widely advised where optional.
Does UIM pay for car damage?
Often yes via "UMPD," but rules vary — some states require collision to cover it instead. Check your policy.